*{
	padding: 0;margin: 0;
}
li{
	list-style: none;
}
a{
	text-decoration: none;
}
.nav{
	width: 100%;
	height: 40px;
	background: #222;
	margin-top: 100px;
	
}
.nav .list{
	width: 1000px;
	height: 40px;
	margin: 0 auto;
}
.nav .list li{
	float: left;
	position: relative;

}
.nav .list li>a {
	display: block;
	color: #aaa;
	padding: 0 30px;
	transition: 0.5s;
	line-height: 40px;
	font-size:16px ;
}
.nav .list li:hover>a{
	background: #333;
	color: #fff;
}

.nav .list .down{
	width: 150px;
	background: #333;
	position: absolute;
	top: 40;
	display: none;
    /*transition: 0.2s;
	opacity: 0;*/
	left: 0;
}
.list li:hover .down{
	opacity: 1;
	display: block;
}
.nav .list .down a{
	display: block;
	line-height: 30px;
	color: #aaa;
	padding: 0 30px;
	font-size: 14px;
}
.nav .list .down a:hover{
		background: #333;
	color: #fff;
}
